Validation of a model of colon cancer progression

A unique feature of SW480 and SW620 colon carcinoma cell lines is that they are derived from primary and secondary tumours resected from a single pati ent. As such, they may represent a valuable resource for examining genetic changes late in colon cancer progression. In order to verify this, both cel l lines have been characterized to determine whether phenotypic differences have been retained despite long-term cell culture in vitro. The primary tu mour-derived SW480 cells have an epithelioid morphology in vitro, while met astasis-derived SW620 cells have a fibroblast-like appearance, Xenografts o f SW480 cells form gland-like structures irt vivo, while SW620 xenografts f orm solid sheets of tumour cells, SW620 cells have a higher BrdU labelling index than SW480 cells, and are more highly tumourigenic and metastatic, Fu rthermore, SW620 cells show less susceptibility to apoptosis induction by T NF alpha and anti-Fas monoclonal, Findings from these investigations theref ore indicate that SW480 and SW620 cell lines do show appropriate phenotypic differences and represent an interesting model for studying the genetic ev ents in the late stages of colon cancer progression. Copyright (C) 2000 Joh n Wiley & Sons, Ltd.